I'm wondering if there are suttas that explain the 4 aspects of right effort, sammāvāyāmo, in more detail. does this sutta suffice? Or are there slight differences between the 4 right exertions in 37 bodhipakkiya and the 4 aspects of sammāvāyāmo? What makes me wonder is that for the 4th exertion, doing contemplation of corpses is not really the first thing that would come to my mind if given the general instruction (of right effort) to maintain wholesome qualities that have arisen. So I'm wondering if there are other suttas that explain sammāvāyāmo using different examples than the specific kusala and akusala themes used in this sutta.

Endeavour, to restrain, to dispel, to develop and the endeavour to protect.

Bhikkhus, what is the endeavour to restrain?

Here, bhikkhus, the bhikkhu seeing a form does not take the sign or the detail. If abiding with the faculty of the eye uncontrolled, there would be a leaking of evil demeritorious thoughts of covetousness and displeasure, he falls to the method of protecting the faculty of the eye. Hearing a sound, ... re ... smelling a scent ... re ... ñasting, ... re ... cognizing a touch or cognizing an idea, does not take the sign or the detail. If abiding with the faculty of the mind uncontrolled, there would be a leaking of evil demeritorious thoughts of covetousness and displeasure, he falls to the method of protecting the faculty of the mind.

Here, bhikkhus, the bhikkhu protects the arisen good sign of concentration, the sign of bones, the sign of, the worm infested corpse, the corpse turned blue, the festering corpse, the corpse with little holes all over, the bloated corpse.

Bhikkhus, this is the endeavour to protect.

Restraining, dispelling, developing and protecting,Are the four endeavours declared by the kinsman of the sun.If the bhikkhu becomes zealous in them he destroys unpleasantness.

frank k wrote:I'm wondering if there are suttas that explain the 4 aspects of right effort, sammāvāyāmo, in more detail.

Samvara sutta you cited gives the most detail.

Or are there slight differences between the 4 right exertions in 37 bodhipakkiya and the 4 aspects of sammāvāyāmo?

No difference.

What makes me wonder is that for the 4th exertion, doing contemplation of corpses is not really the first thing that would come to my mind if given the general instruction (of right effort) to maintain wholesome qualities that have arisen.

Well, such was the ancient practice. And these are just examples of representations of concentration (samadhi-nimitta).Samadhi-nimitta is to be kept in mind with remembrance (sati) for days and weeks. This is the essential tool for maintaining skilful (mental) behavior (kusala-dhamma).

"I asked, "Do you recommend taking one part of the body, the skeleton for instance, as a fixed object of samadhi?""Yes, you can certainly do that. If at first you can't visualize your bones it may be necessary to go look at a skeleton. Remember what it looks like. Then imagine yourself as a skeleton. Take the skeleton out of yourself, then put yourself in the skeleton. With increasing skill, each time you are aware of yourself you can bring up the skeleton nimitta, (in this context) visual images of the body, either created or spontaneously arisen, or actually seeing into the body with the mind's eye, knowing 'you' are bones. Then when the nimitta is clear and stable,break it up and dissolve it into dust and anatta. If you use this as your main mode of investigation, each person you encounter or think of, you must see as a skeleton. When skilled, this will bring lightness and bliss. This is the way I practised as a young monk."

"Should one investigate in the same manner each time or follow wherever the mind inclines?""Any part of the body is fine. If the mind goes to a particular spot then contemplate there. If distracting thoughts begin to increase, let the mind rest by returning to concentration meditation. After it has regained strength continue with the contemplation. Whichever part is clear, a tooth for example, make that nimitta as big or as small as possible. I used to take a tiny single hair and make it longer and longer until it filled all space. Then I'd shrink it. It was good fun and I'd do it for hours. This type of fun is quite useful because you are playing with the meditation objects of hair, skin, bones etc. the entire time. It is important to enjoy meditation, or else one will inevitably begin looking outside for enjoyment."

In the following years the mental image of Sleeping Beauty's far from charming lineaments remained vivid and clear. And she taught: when the grand ball is over, the last dance has come to a halt and our mask is gently rolled back, what's behind our thin facade? The kiss of the coroner's blade invites us to awaken. "

There is the case where a monk, a disciple of the noble ones, keeps his persistence aroused for abandoning unskillful mental qualities and taking on skillful mental qualities. He is steadfast, solid in his effort, not shirking his duties with regard to skillful mental qualities.

He generates desire, endeavors, arouses persistence, upholds & exerts his intent for the sake of the non-arising of evil, unskillful qualities that have not yet arisen... for the sake of the abandoning of evil, unskillful qualities that have arisen... for the sake of the arising of skillful qualities that have not yet arisen...(and) for the maintenance, non-confusion, increase, plenitude, development, & culmination of skillful qualities that have arisen.

Thanks Dmytro, that is an awesome quote on how that (4th sammāvāyamo) is actually practiced.So Viriya as one of 7 sambojjhanga is also exactly equivalent to right effort (of noble 8fold path), 4 right exertions (of 37 bodhipakkiya)?

Wow , that is some serious redundancy and recursion going on.In the canonical sammāvāyamo, you have the words viriyam arabhati, and padhahati. I never saw all those connections until I started looking at the pali instead of relying on english translations.